Ethylene-based polymers and processes to make the same

ABSTRACT

An ethylene-based polymer, which is a low density polyethylene (LDPE), obtained by free radical polymerization of ethylene, and wherein the LDPE has a GPC parameter “LSP” less than 1.60. 
     An ethylene-based polymer that comprises the following features:
         a) at least 0.1 amyl groups per 1000 total carbon atoms;   b) a melt index of 0.01 to 0.3;   c) a z-average molecular weight of Mz (conv.) of greater than 350,000 g/mol and less than 425,000 g/mol;   d) a gpcBR value from 1.50 to 2.05, and   e) a MWD(conv) [Mw(conv)/Mn(conv)] from 6 to 9.       

     An ethylene-based polymer that comprises the following features:
         a) at least 0.1 amyl groups per 1000 total carbon atoms;   b) a melt viscosity ratio (V0.1/V100), at 190° C., greater than, or equal to, 58;   c) a melt viscosity at 0.1 rad/s, 190° C., greater than, or equal to, 40,000 Pa·s, and   d) a gpcBR value from 1.50 to 2.25.

REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/707,342, filed on Sep. 28, 2012.

BACKGROUND OF THE INVENTION

Blown film production lines are typically limited in output by bubblestability. Blending Linear Low Density Polyethylene (LLDPE) with 0.5 wt%-90 wt % of Low Density Polyethylene (LDPE) increases bubble stability,in part due to the higher melt strength of the LDPE. The increase inmelt strength in part provides for an increase in film output. However,too high a melt strength can cause gels and poor quality film, as wellas potentially limiting drawdown capabilities to thinner gauges (0.5 to1 mil film). High melt strength resins also typically have reducedoptics and toughness properties. Thus, there is a need for newethylene-based polymers, such as LDPEs, that have an optimized balanceof melt strength and improved film optical and mechanical properties,for blown film applications.

LDPE polymers are disclosed in the following references: WO 2010/042390,WO 2010/144784, WO 2011/019563, WO 2012/082393, WO 2006/049783, WO2009/114661, US 2008/0125553, U.S. Pat. No. 7,741,415, and EP 2239283B1.However, such polymers do not provide an optimized balance of high meltstrength and improved film mechanical properties, for blown filmapplications. Thus, as discussed above, there remains a need for newethylene-based polymers, such as LDPEs, that have an optimized balanceof melt strength, optics, processability and output, and toughness.These needs and others have been met by the following invention.

SUMMARY OF THE INVENTION

The invention provides a composition comprising an ethylene-basedpolymer, which is a low density polyethylene (LDPE), obtained by freeradical polymerization of ethylene, and wherein the LDPE has aGPC-parameter “LSP” less than 1.60.

The invention also provides a composition comprising an ethylene-basedpolymer that comprises the following features:

a) at least 0.1 amyl groups per 1000 total carbon atoms;

b) a melt index of 0.01 to 0.3;

c) a z-average molecular weight of Mz (conv) of greater than 350,000g/mol and less than 425,000 g/mol;

d) a gpcBR value from 1.50 to 2.05, and

e) a MWD(conv) [Mw(conv)/Mn(conv)] from 6 to 9.

The invention also provides a composition comprising an ethylene-basedpolymer that comprises the following features:

a) at least 0.1 amyl groups per 1000 total carbon atoms;

b) a melt viscosity ratio (V0.1/V100), at 190° C., greater than, orequal to, 58;

c) a melt viscosity at 0.1 rad/s, 190° C., greater than, or equal to,40,000 Pa·s, and

d) a gpcBR value from 1.50 to 2.25.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts a GPC LS (light scattering) profile of Example 1.

FIG. 2 depicts a GPC LS (light scattering) profile of Example 2.

FIG. 3 depicts a GPC LS (light scattering) profile of ComparativeExample 1.

FIG. 4 depicts a block diagram of the process reaction system used toproduce the Inventive Examples.

DETAILED DESCRIPTION

Novel ethylene-based polymers, such as LDPEs, were developed withoptimized melt strength to increase processability and output; allowdrawability to thin gauges; minimize gels when blended with otherpolymers, and improve toughness relative to current LDPE products.

As discussed above, in a first aspect, the invention provides acomposition comprising a low density polyethylene (LDPE) obtained byfree radical polymerization of ethylene, and wherein the LDPE has aGPC-Light Scattering Parameter “LSP” less than 1.60.

The composition may comprise a combination of two or more embodiments asdescribed herein.

The LDPE may comprise a combination of two or more embodiments asdescribed herein.

In one embodiment, the LDPE has a GPC-Light Scattering parameter “LSP”less than 1.50, further less than 1.40, and further less than 1.35.

In one embodiment, the LDPE has a GPC-Light Scattering parameter “LSP”from 0.1. to 1.6, further from 0.3 to 1.4, and further from 0.9 to 1.2.

In one embodiment, the LDPE has at least 0.1 amyl groups per 1000 totalcarbon atoms.

In one embodiment, the LDPE has a gpcBR value from 1.50 to 2.25.

In one embodiment, the LDPE has a viscosity ratio (V0.1/V100, at 190°C.) greater than, or equal to, 50, further greater than, or equal to,52.

In a second aspect, the invention provides a composition comprising anethylene-based polymer that comprises the following features:

a) at least 0.1 amyl groups per 1000 total carbon atoms;

b) a melt index of 0.01 to 0.3;

c) a z-average molecular weight of Mz (conv) of greater than 350,000g/mol and less than 425,000 g/mol;

d) a gpcBR value from 1.50 to 2.05, and

e) a MWD(conv) [Mw(conv)/Mn(conv)] from 6 to 9.

In a third aspect, the invention provides a composition comprising anethylene-based polymer that comprises the following features;

a) at least 0.1 amyl groups per 1000 total carbon atoms;

b) a melt viscosity ratio (V0.1/V100), at 190° C., greater than, orequal to, 58;

c) a melt viscosity at 0.1 rad/s, 190° C., greater than, or equal to,40,000 Pa·s, and

d) a gpcBR value from 1.50 to 2.25.

The following embodiments apply to the second and third aspects(compositions) of the invention.

The composition may comprise a combination of two or more embodiments asdescribed herein.

The ethylene-based polymer may comprise a combination of two or moreembodiments as described herein.

In one embodiment, the ethylene-based polymer has a GPC-Light Scatteringparameter “LSP” less than 2.0.

In one embodiment, the polymer has a viscosity ratio (V0.1/V100, at 190°C.) greater than, or equal to, 50, further greater than, or equal to,52.

The following embodiments apply to all three aspects (compositions) ofthe invention.

In one embodiment, the polymer has a MWD(conv) from 5 to 8.

In one embodiment, the polymer has a melt strength (MS) greater than 15cN and less than 25 cN.

In one embodiment, the polymer has a melt strength of at least 15 cN andless than 21 cN, and a velocity at break of greater than 40 mm/s.

In one embodiment, the polymer has a viscosity ratio (V0.1/V100, at 190°C.) greater than, or equal to, 50, further greater than, or equal to,55, further greater than, or equal to, 59, further greater than, orequal to, 60.

In one embodiment, the polymer has a MWD(conv) greater than 6.

In one embodiment, the polymer has a melt viscosity at 0.1 rad/s, 190°C., greater than, or equal to, 42,000 Pa·s, further greater than, orequal to, 45,000 Pa·s.

In one embodiment, the polymer has a density from 0.910 to 0.940 g/cc,further from 0.910 to 0.930 g/cc, further from 0.915 to 0.925 g/cc, andfurther from 0.916 to 0.922 g/cc (1 cc=1 cm³).

In one embodiment, the polymer has a cc-GPC Mw from 75,000 g/mol to175,000 g/mol, further from 100,000 to 150,000 g/mol, and further from115,000 g/mol to 140,000 g/mol.

In one embodiment, the polymer has a cc-GPC Mz from 300,000 to 500,000g/mol, further from 350,000 g/mol to 450,000 g/mol, and further from375,000 g/mol to 425,000 g/mol.

In one embodiment, the polymer has a Mw-abs from 200,000 g/mol to350,000 g/mol, further from 225,000 g/mol to 325,000 g/mol, and furtherfrom 250,000 g/mol to 300,000 g/mol.

In one embodiment, the polymer has a Mw(LS-abs)/Mw(cc-GPC) from 1 to 3,further from 1.5 to 2.75, and further from 1.9 to 2.4.

In one embodiment, the polymer has an IVw from 1.00 dl/g to 1.30 dl/g,further from 1.05 dl/g to 1.25 dl/g, and further from 1.1 dl/g to 1.2dl/g.

In one embodiment, the polymer has an IVcc from 1.4 dl/g to 2.5 dl/g,further from 1.6 to 2.25 dl/g, and further from 1.7-2.1 dl/g.

In one embodiment, the polymer has an IVcc/IVw from 1.2 to 2.2, furtherfrom 1.4 to 1.9, and further from 1.6 to 1.7.

In one embodiment, the polymer has greater than, or equal to, 0.2 amylgroups (branches) per 1000 carbon atoms, further greater than, or equalto, 0.5 amyl groups per 1000 carbon atoms, further greater than, orequal to, 1 amyl groups per 1000 carbon atoms, and further greater than,or equal to, 1.4 amyl groups per 1000 carbon atoms.

In one embodiment, the polymer has a rheology ratio (V0.1/V100), at 190°C., from 40 to 80, further from 45 to 70, and further from 50 to 65.

In one embodiment, the polymer has a tan delta (measured at 0.1 rad/s at190° C.) less than, or equal to 2.0, further less than, or equal to1.75, and further than, or equal to 1.50.

In one embodiment, the polymer has a tan delta (measured at 0.1 rad/s)from 0.5 to 2, further from 0.75 to 1.75, and further from 1 to 1.5.

In one embodiment, the polymer has a viscosity at 0.1 rad/s and 190° C.from 30,000 Pa·s to 80,000 Pa·s, further from 40,000 Pa·s to 70,000Pa·s, and further from 45,000 Pa·s to 60,000 Pa·s.

In one embodiment, the polymer is formed in a high pressure (P greaterthan 100 MPa) polymerization process.

In one embodiment, the polymer is a low density polyethylene (LDPE),obtained by the high pressure (P greater than 100 MPa), free radicalpolymerization of ethylene.

In one embodiment, the polymer is a low density polyethylene (LDPE).

In one embodiment, the polymer is present at greater than, or equal to,10 weight percent, based on the weight of the composition.

In one embodiment, the polymer is present in an amount from 10 to 50weight percent, further from 20 to 40 weight percent, based on theweight of the composition.

In one embodiment, the polymer is present in an amount from 60 to 90weight percent, further from 65 to 85 weight percent, based on theweight of the composition.

In one embodiment, the polymer is present in an amount from 1 to 10weight percent, further from 1.5 to 5 weight percent, based on theweight of the composition.

In one embodiment, the composition further comprises anotherethylene-based polymer. Suitable other ethylene-based polymers include,but are not limited to, DOWLEX Polyethylene Resins, TUFLIN Linear LowDensity Polyethylene Resins, ELITE or ELITE AT Enhanced PolyethyleneResins (all available from The Dow Chemical Company), high densitypolyethylenes (d≧0.96 g/cc), medium density polyethylenes (density from0.935 to 0.955 g/cc), EXCEED polymers and ENABLE polymers (both fromExxonMobil), LDPE, and EVA (ethylene vinyl acetate).

In one embodiment, the composition further comprises anotherethylene-based polymer that differs in one or more properties, such asdensity, melt index, comonomer, comonomer content, etc., from theinventive polymer. Suitable other ethylene-based polymers include, butare not limited to, DOWLEX Polyethylene Resins (LLDPEs), TUFLIN LinearLow Density Polyethylene Resins, ELITE or ELITE AT Enhanced PolyethyleneResins (all available from The Dow Chemical Company), high densitypolyethylenes (d≧0.96 g/cc), medium density polyethylenes (density from0.935 to 0.955 g/cc), EXCEED polymers and ENABLE polymers (both fromExxonMobil), LDPE, and EVA (ethylene vinyl acetate).

In one embodiment, the composition further comprises a propylene-basedpolymer. Suitable propylene-based polymers include polypropylenehomopolymers, propylene/α-olefin interpolymers, and propylene/ethyleneinterpolymers.

In one embodiment, the composition further comprises a heterogeneouslybranched ethylene/α-olefin interpolymer, and preferably aheterogeneously branched ethylene/α-olefin copolymer. In one embodiment,the heterogeneously branched ethylene/α-olefin interpolymer, andpreferably a heterogeneously branched ethylene/α-olefin copolymer, has adensity from 0.89 to 0.94 g/cc, further from 0.90 to 0.93 g/cc. In afurther embodiment, the composition comprises 1 to 99 weight percent,further from 15 to 85 weight percent, of the inventive ethylene-basedpolymer, based on the weight of the composition.

In one embodiment, the composition comprises less than 5 ppm, furtherless than 2 ppm, further less than 1 ppm, and further less than 0.5 ppmsulfur, based on the weight of the composition.

In one embodiment, the composition does not contain sulfur.

In one embodiment, the composition comprises from 1.5 to 80 weightpercent of an inventive polymer. In a further embodiment, thecomposition further comprises a LLDPE (Linear Low Density Polyethylene).

In one embodiment, the composition comprises from 1.5 to 20 weightpercent an inventive polymer. In a further embodiment, the compositionfurther comprises a LLDPE.

In one embodiment, the composition comprises from 20 to 80 weightpercent, further from 50 to 80 weight percent an inventive polymer. In afurther embodiment, the composition further comprises a LLDPE.

An inventive composition may comprise a combination of two or moreembodiments as described herein.

In one embodiment, for the first and third aspects, the polymer has amelt index (12) from 0.01 to 10 g/10 min, further from 0.05 to 5 g/10min, and further from 0.05 to 0.5 g/10 min.

In one embodiment, for the first and third aspects, the polymer has amelt index (12) from 0.01 to 1.5 g/10 min, further from 0.05 to 1.0 g/10min, and further from 0.05 to 0.25 g/10 min.

In one embodiment, for the first and third aspects, the polymer has amelt index (12) from 0.01 to 1 g/10 min.

In one embodiment, for the first and third aspects, the polymer has amelt index (12) less than or equal to 0.5.

In one embodiment, for the first and third aspects, the polymer has arheology ratio (V0.1/V100), at 190° C., greater than, or equal to 40,further greater than, or equal to 45, further greater than, or equal to50, and further greater than, or equal to 55.

The invention also provides an article comprising at least one componentformed from an inventive composition. In a further embodiment, thearticle is a film. In another embodiment, the article is a coating.

The invention also provides a process for forming an inventiveethylene-based polymer of any of the previous embodiments, the processcomprising polymerizing ethylene, and optionally at least one comonomer,in at least one autoclave reactor.

The invention also provides a process for forming a polymer of any ofthe previous embodiments, the process comprising polymerizing ethylene,and optionally at least one comonomer, in at least one tubular reactor.

The invention also provides a process for forming an inventiveethylene-based polymer of any of the previous embodiments, the processcomprising polymerizing ethylene, and optionally at least one comonomer,in a combination of at least one tubular reactor and at least oneautoclave reactor.

An inventive composition may comprise a combination of two or moreembodiments as described herein.

An inventive ethylene-based polymer may comprise a combination of two ormore embodiments as described herein.

An inventive article may comprise a combination of two or moreembodiments as described herein. An inventive film may comprise acombination of two or more embodiments as described herein.

An inventive process may comprise a combination of two or moreembodiments as described herein.

Process

For producing an inventive ethylene-based polymer, including aninventive LDPE, a high pressure, free-radical initiated polymerizationprocess is typically used. Two different high pressure, free-radicalinitiated polymerization process types are known. In the first type, anagitated autoclave vessel having one or more reaction zones is used. Theautoclave reactor normally has several injection points for initiator ormonomer feeds, or both. In the second type, a jacketed tube is used as areactor, which has one or more reaction zones. Suitable, but notlimiting, reactor lengths may be from 100 to 3000 meters (m), or from1000 to 2000 meters. The beginning of a reaction zone for either type ofreactor is typically defined by the side injection of either initiatorof the reaction, ethylene, chain transfer agent (or telomer),comonomer(s), as well as any combination thereof. A high pressureprocess can be carried out in autoclave or tubular reactors, each havingone or more reaction zones, or in a combination of autoclave and tubularreactors, each comprising one or more reaction zones.

A chain transfer agent can be used to control molecular weight. In apreferred embodiment, one or more chain transfer agents (CTAs) are addedto an inventive polymerization process. Typical CTA's that can be usedinclude, but are not limited to, propylene, isobutane, n-butane,1-butene, methyl ethyl ketone, acetone, and propionaldehyde. In oneembodiment, the amount of CTA used in the process is from 0.03 to 10weight percent of the total reaction mixture.

Ethylene used for the production of the ethylene-based polymer may bepurified ethylene, which is obtained by removing polar components from aloop recycle stream, or by using a reaction system configuration, suchthat only fresh ethylene is used for making the inventive polymer. It isnot typical that only purified ethylene is required to make theethylene-based polymer. In such cases ethylene from the recycle loop maybe used.

In one embodiment, the ethylene-based polymer is a polyethylenehomopolymer.

In another embodiment, the ethylene-based polymer comprises ethylene andone or more comonomers, and preferably one comonomer. Comonomersinclude, but are not limited to, α-olefin comonomers, typically havingno more than 20 carbon atoms. For example, the α-olefin comonomers mayhave 3 to 10 carbon atoms, further 3 to 8 carbon atoms. Exemplaryα-olefin comonomers include, but are not limited to, propylene,1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene,and 4-methyl-1-pentene. In the alternative, exemplary comonomersinclude, but are not limited to α,β-unsaturated C3-C8-carboxylic acids(for example, maleic acid, fumaric acid, itaconic acid, acrylic acid,methacrylic acid), crotonic acid derivatives of the α,β-unsaturatedC3-C8-carboxylic acids (for example, unsaturated C3-C15-carboxylic acidesters, in particular ester of C1-C6-alkanols, or anhydrides), methylmethacrylate, ethyl methacrylate, n-butyl methacrylate, ter-butylmethacrylate, methyl acrylate, ethyl acrylate, n-butyl acrylate,2-ethylhexyl acrylate, tert-butyl acrylate, methacrylic anhydride,maleic anhydride, and itaconic anhydride. In another alternative, theexemplary comonomers include, but are not limited to, vinylcarboxylates, for example vinyl acetate. In another alternative,exemplary comonomers include, but are not limited to, n-butyl acrylate,acrylic acid and methacrylic acid.

Additives

An inventive composition may comprise one or more additives. Additivesinclude, but are not limited to, stabilizers, plasticizers, antistaticagents, pigments, dyes, nucleating agents, fillers, slip agents, fireretardants, processing aids, smoke inhibitors, viscosity control agentsand anti-blocking agents. The polymer composition may, for example,comprise less than 10 percent (by the combined weight) of one or moreadditives, based on the weight of the inventive polymer composition.

In one embodiment, the polymers of this invention are treated with oneor more stabilizers, for example, antioxidants, such as IRGANOX 1010,IRGANOX 1076 and IRGAFOS 168 (Ciba Specialty Chemicals; Glattbrugg,Switzerland). In general, the polymers are treated with one or morestabilizers before extrusion or other melt processes. Processing aids,such as plasticizers, include, but are not limited to, the phthalates,such as dioctyl phthalate and diisobutyl phthalate, natural oils such aslanolin, and paraffin, naphthenic and aromatic oils obtained frompetroleum refining, and liquid resins from rosin or petroleumfeedstocks. Exemplary classes of oils, useful as processing aids,include white mineral oil such as KAYDOL oil (Chemtura Corp.;Middlebury, Conn.) and SHELLFLEX 371 naphthenic oil (Shell Lubricants;Houston, Tex.). One other suitable oil is TUFFLO oil (LyondellLubricants; Houston, Tex.).

Blends and mixtures of the inventive polymer with other polymers may beperformed. Suitable polymers for blending with the inventive polymerinclude natural and synthetic polymers. Exemplary polymers for blendinginclude propylene-based polymers (both impact modifying polypropylene,isotactic polypropylene, atactic polypropylene, and randomethylene/propylene copolymers), various types of ethylene-basedpolymers, including high pressure, free-radical LDPE, LLDPE preparedwith Ziegler-Natta catalysts, PE prepared with single site catalysts,including multiple reactor PE (“in reactor” blends of Ziegler-Natta PEand single site catalyzed PE, such as products disclosed in U.S. Pat.No. 6,545,088 (Kolthammer et al.); U.S. Pat. No. 6,538,070 (Cardwell, etal.); U.S. Pat. No. 6,566,446 (Parikh, et al.); U.S. Pat. No. 5,844,045(Kolthammer et al.); U.S. Pat. No. 5,869,575 (Kolthammer et al.); andU.S. Pat. No. 6,448,341 (Kolthammer et al.)), EVA, ethylene/vinylalcohol copolymers, polystyrene, impact modified polystyrene, ABS,styrene/butadiene block copolymers and hydrogenated derivatives thereof(SBS and SEBS), and thermoplastic polyurethanes. Homogeneous polymers,such as olefin plastomers and elastomers, ethylene and propylene-basedcopolymers (for example, polymers available under the trade designationVERSIFY Plastomers & Elastomers (The Dow Chemical Company) and VISTAMAXX(ExxonMobil Chemical Co.) can also be useful as components in blendscomprising the inventive polymer).

Applications

The polymers of this invention may be employed in a variety ofconventional thermoplastic fabrication processes to produce usefularticles, including, but not limited to, monolayer and multilayer films;molded articles, such as blow molded, injection molded, or rotomoldedarticles; coatings; fibers; and woven or non-woven fabrics.

An inventive polymer may be used in a variety of films, including butnot limited to, extrusion coating, food packaging, consumer, industrial,agricultural (applications or films), lamination films, fresh cutproduce films, meat films, cheese films, candy films, clarity shrinkfilms, collation shrink films, stretch films, silage films, greenhousefilms, fumigation films, liner films, stretch hood, heavy duty shippingsacks, pet food, sandwich bags, sealants, and diaper backsheets.

An inventive polymer is also useful in other direct end-useapplications. An inventive polymer may be used for wire and cablecoating operations, in sheet extrusion for vacuum forming operations,and forming molded articles, including the use of injection molding,blow molding process, or rotomolding processes.

Other suitable applications for the inventive polymers include elasticfilms and fibers; soft touch goods, such as appliance handles; gasketsand profiles; auto interior parts and profiles; foam goods (both openand closed cell); impact modifiers for other thermoplastic polymers,such as high density polyethylene, or other olefin polymers; cap liners;and flooring.

DEFINITIONS

The term “polymer,” as used herein, refers to a polymeric compoundprepared by polymerizing monomers, whether of the same or a differenttype. The generic term polymer thus embraces the term homopolymer(employed to refer to polymers prepared from only one type of monomer,with the understanding that trace amounts of impurities can beincorporated into the polymer structure), and the term interpolymer asdefined hereinafter. Trace amounts of impurities may be incorporatedinto and/or within a polymer.

The term “interpolymer,” as used herein, refers to polymers prepared bythe polymerization of at least two different types of monomers. Thegeneric term interpolymer includes copolymers (employed to refer topolymers prepared from two different types of monomers), and polymersprepared from more than two different types of monomers.

The term “ethylene-based polymer,” as used herein, refers to a polymerthat comprises a majority amount of polymerized ethylene monomer (basedon weight of the polymer) and, optionally, may contain at least onecomonomer.

The term “ethylene/α-olefin interpolymer,” as used herein, refers to aninterpolymer that comprises a majority amount of polymerized ethylenemonomer (based on the weight of the interpolymer) and at least oneα-olefin.

The term, “ethylene/α-olefin copolymer,” as used herein, refers to acopolymer that comprises a majority amount of polymerized ethylenemonomer (based on the weight of the copolymer), and an α-olefin, as theonly two monomer types.

The term “propylene-based polymer,” as used herein, refers to a polymerthat comprises a majority amount of polymerized propylene monomer (basedon weight of the polymer) and, optionally, may comprise at least onecomonomer.

The term “composition,” as used herein, includes a mixture of materialswhich comprise the composition, as well as reaction products anddecomposition products formed from the materials of the composition.

The terms “blend” or “polymer blend,” as used, refers to a mixture oftwo or more polymers. A blend may or may not be miscible (not phaseseparated at the molecular level). A blend may or may not be phaseseparated. A blend may or may not contain one or more domainconfigurations, as determined from transmission electron spectroscopy,light scattering, x-ray scattering, and other methods known in the art.The blend may be effected by physically mixing the two or more polymerson the macro level (for example, melt blending resins or compounding) orthe micro level (for example, simultaneous forming within the samereactor).

The terms “comprising,” “including,” “having,” and their derivatives,are not intended to exclude the presence of any additional component,step or procedure, whether or not the same is specifically disclosed. Inorder to avoid any doubt, all compositions claimed through use of theterm “comprising” may include any additional additive, adjuvant, orcompound, whether polymeric or otherwise, unless stated to the contrary.In contrast, the term, “consisting essentially of” excludes from thescope of any succeeding recitation any other component, step orprocedure, excepting those that are not essential to operability. Theterm “consisting of” excludes any component, step or procedure notspecifically delineated or listed.

TEST METHODS

Density

Samples for density measurements were prepared according to ASTM D4703-10. Samples were pressed at 374° F. (190° C.) for five minutes at10,000 psi (68 MPa). The temperature was maintained at 374° F. (190° C.)for the above five minutes, and then the pressure was increased to30,000 psi (207 MPa) for three minutes. This was followed by a oneminute hold at 70° F. (21° C.) and 30,000 psi (207 MPa). Measurementswere made within one hour of sample pressing using ASTM D792-08, MethodB.

Melt Index

Melt index, or 12, was measured in accordance with ASTM D 1238-10,Condition 190° C./2.16 kg, Method A, and was reported in grams elutedper 10 minutes.

Nuclear Magnetic Resonance (¹³C NMR)

Samples were prepared by adding approximately “3 g of a 50/50 mixture oftetrachloroethane-d2/orthodichlorobenzene, containing 0.025 MCr(AcAc)₃,” to a “0.25 to 0.40 g polymer sample,” in a 10 mm NMR tube.Oxygen was removed from the sample by placing the open tubes in anitrogen environment for at least 45 minutes. The samples were thendissolved and homogenized by heating the tube, and its contents to 150°C., using a heating block and heat gun. Each dissolved sample wasvisually inspected to ensure homogeneity. Samples were thoroughly mixed,immediately prior to analysis, and were not allowed to cool beforeinsertion into the heated NMR sample holders.

All data were collected using a Bruker 400 MHz spectrometer. The datawas acquired using a six second pulse repetition delay, 90-degree flipangles, and inverse gated decoupling, with a sample temperature of 125°C. All measurements were made on non-spinning samples in locked mode.Samples were allowed to thermally equilibrate for seven minutes prior todata acquisition. The ¹³C NMR chemical shifts were internally referencedto the EEE triad at 30.0 ppm. The C6+ value was a direct measure of C6+branches in LDPE, where the long branches were not distinguished fromchain ends. The 32.2 ppm peak, representing the third carbon from theend of all chains or branches of six or more carbons, was used todetermine the C6+ value.

Nuclear Magnetic Resonance (¹H NMR)

Sample Preparation

The samples were prepared by adding approximately 130 mg of sample to“3.25 g of 50/50, by weight, tetrachlorethane-d2/perchloroethylene” with0.001 M Cr(AcAc)₃ in a NORELL 1001-7, 10 mm NMR tube. The samples werepurged by bubbling N₂ through the solvent, via a pipette inserted intothe tube, for approximately five minutes, to prevent oxidation. Eachtube was capped, sealed with TEFLON tape, and then soaked at roomtemperature, overnight, to facilitate sample dissolution. The sampleswere kept in a N₂ purge box, during storage, before, and after,preparation, to minimize exposure to O₂. The samples were heated andvortexed at 115° C. to ensure homogeneity.

Data Acquisition Parameters

The ¹H NMR was performed on a Bruker AVANCE 400 MHz spectrometer,equipped with a Bruker Dual DUL high-temperature CryoProbe, and a sampletemperature of 120° C. Two experiments were run to obtain spectra, acontrol spectrum to quantitate the total polymer protons, and a doublepresaturation experiment, which suppressed the intense polymer backbonepeaks, and enabled high sensitivity spectra for quantitation of theend-groups. The control was run with ZG pulse, 4 scans, SWH 10,000 Hz,AQ 1.64 s, D1 14 s. The double presaturation experiment was run with amodified pulse sequence, TD 32768, 100 scans, DS 4, SWH 10,000 Hz, AQ1.64 s, D1 1 s, D13 13 s.

Data Analysis-¹H NMR Calculations

The signal from residual ¹H in TCE-d2 (at 6.0 ppm) was integrated, andset to a value of 100, and the integral from 3 to −0.5 ppm was used asthe signal from the whole polymer in the control experiment. For thepresaturation experiment, the TCE signal was also set to 100, and thecorresponding integrals for unsaturation (vinylene at about 5.40 to 5.60ppm, trisubstituted at about 5.16 to 5.35 ppm, vinyl at about 4.95 to5.15 ppm, and vinylidene at about 4.70 to 4.90 ppm) were obtained.

In the presaturation experiment spectrum, the regions for cis- andtrans-vinylene, trisubstituted, vinyl, and vinylidene were integrated.The integral of the whole polymer from the control experiment wasdivided by two, to obtain a value representing X thousands of carbons(i.e., if the polymer integral=28,000, this represents 14,000 carbons,and X=14).

The unsaturated group integrals, divided by the corresponding number ofprotons contributing to that integral, represent the moles of each typeof unsaturation per X thousand carbons. Dividing the moles of each typeof unsaturation by X, then gives moles unsaturated groups per 1,000moles of carbons.

Melt Strength

Melt strength measurements were conducted on a Gottfert Rheotens 71.97(Göettfert Inc.; Rock Hill, S.C.), attached to a Gottfert Rheotester2000 capillary rheometer. The melted sample (about 25 to 30 grams) wasfed with a Göettfert Rheotester 2000 capillary rheometer, equipped witha flat entrance angle (180 degrees) of length of 30 mm, diameter of 2.0mm, and an aspect ratio (length/diameter) of 15. After equilibrating thesamples at 190° C. for 10 minutes, the piston was run at a constantpiston speed of 0.265 mm/second. The standard test temperature was 190°C. The sample was drawn uniaxially to a set of accelerating nips,located 100 mm below the die, with an acceleration of 2.4 mm/s². Thetensile force was recorded as a function of the take-up speed of the niprolls. Melt strength was reported as the plateau force (cN) before thestrand broke. The following conditions were used in the melt strengthmeasurements: plunger speed=0.265 mm/second; wheel acceleration=2.4mm/s²; capillary diameter=2.0 mm; capillary length=30 mm; and barreldiameter=12 mm

Dynamic Mechanical Spectroscopy (DMS)

Resins were compression-molded into “3 mm thick×1 inch” circular plaquesat 350° F., for five minutes, under 1500 psi pressure, in air. Thesample was then taken out of the press, and placed on the counter tocool.

A constant temperature frequency sweep was performed using a TAInstruments “Advanced Rheometric Expansion System (ARES),” equipped with25 mm (diameter) parallel plates, under a nitrogen purge. The sample wasplaced on the plate, and allowed to melt for five minutes at 190° C. Theplates were then closed to a gap of 2 mm, the sample trimmed (extrasample that extends beyond the circumference of the “25 mm diameter”plate was removed), and then the test was started. The method had anadditional five minute delay built in, to allow for temperatureequilibrium. The experiments were performed at 190° C., over a frequencyrange of 0.1 to 100 rad/s. The strain amplitude was constant at 10%. Thecomplex viscosity η*, tan (δ) or tan delta, viscosity at 0.1 rad/s(V0.1), the viscosity at 100 rad/s (V100), and the viscosity ratio(V0.1/V100) were calculated from these data.

Triple Detector Gel Permeation Chromatography (TDGPC)—Conventional GPC,Light Scattering GPC, Viscometry GPC and gpcBR

For the GPC techniques used herein (Conventional GPC, Light ScatteringGPC, Viscometry GPC and gpcBR), a Triple Detector Gel PermeationChromatography (3D-GPC or TDGPC) system was used. This system consistsof a Robotic Assistant Delivery (RAD) high temperature GPC system [othersuitable high temperature GPC instruments include Waters (Milford,Mass.) model 150C High Temperature Chromatograph; Polymer Laboratories(Shropshire, UK) Model 210 and Model 220; and Polymer Char GPC-IR(Valencia, Spain)], equipped with a Precision Detectors (Amherst, Mass.)2-angle laser light scattering (LS) detector Model 2040, an IR4infra-red detector from Polymer ChAR (Valencia, Spain), and a4-capillary solution viscometer (DP) (other suitable viscometers includeViscotek (Houston, Tex.) 150R 4-capillary solution viscometer (DP)).

A GPC with these latter two independent detectors and at least one ofthe former detectors is sometimes referred to as “3D-GPC” or “TDGPC,”while the term “GPC” alone generally refers to conventional GPC. Datacollection is performed using Polymer Char GPC-IR software (Valencia,Spain). The system is also equipped with an on-line solvent degassingdevice from Polymer Laboratories (Shropshire, United Kingdom).

The eluent from the GPC column set flows through each detector arrangedin series, in the following order: LS detector, IR4 detector, then DPdetector. The systematic approach for the determination ofmulti-detector offsets is performed in a manner consistent with thatpublished by Balke, Mourey, et al. (Mourey and Balke, ChromatographyPolym., Chapter 12, (1992)) (Balke, Thitiratsakul, Lew, Cheung, Mourey,Chromatography Polym., Chapter 13, (1992)). The triple detector log (MWand intrinsic viscosity) results were optimized using a broadpolyethylene standard, as outlined in the section on Light Scattering(LS) GPC below, in the paragraph following Equation (5).

Suitable high temperature GPC columns can be used, such as four, 30 cm,long Shodex HT803 13 micron columns, or four, 30 cm, Polymer Labscolumns of 13-micron mixed-pore-size packing (Olexis LS, Polymer Labs).Here, the Olexis LS columns were used. The sample carousel compartmentis operated at 140° C., and the column compartment is operated at 150°C. The samples are prepared at a concentration of “0.1 grams of polymerin 50 milliliters of solvent.” The chromatographic solvent and thesample preparation solvent is 1,2,4-trichlorobenzene (TCB) containing200 ppm of 2,6-di-tert-butyl-4methylphenol (BHT). The solvent is spargedwith nitrogen. The polymer samples are gently stirred at 160° C. forfour hours. The injection volume is 200 microliters. The flow ratethrough the GPC is set at 1 ml/minute.

Conventional GPC

For Conventional GPC, the IR4 detector is used, and the GPC column setis calibrated by running 21 narrow molecular weight distributionpolystyrene standards. The molecular weight (MW) of the standards rangesfrom 580 g/mol to 8,400,000 g/mol, and the standards are contained insix “cocktail” mixtures. Each standard mixture has at least a decade ofseparation between individual molecular weights. The standard mixturesare purchased from Polymer Laboratories. The polystyrene standards areprepared at “0.025 g in 50 mL of solvent” for molecular weights equalto, or greater than, 1,000,000 g/mol, and at “0.05 g in 50 mL ofsolvent” for molecular weights less than 1,000,000 g/mol. Thepolystyrene standards are dissolved at 80° C., with gentle agitation,for 30 minutes. The narrow standards mixtures are run first, and inorder of decreasing “highest molecular weight component” to minimizedegradation. The polystyrene standard peak molecular weights areconverted to polyethylene molecular weight using Equation (1) (asdescribed in Williams and Ward, J. Polym. Sci., Polym. Letters, 6, 621(1968)):Mpolyethylene=A×(Mpolystyrene)^(B)  (Eq. 1),where M is the molecular weight of polyethylene or polystyrene (asmarked), and B is equal to 1.0. It is known to those of ordinary skillin the art that A may be in a range of about 0.38 to about 0.44, and isdetermined at the time of calibration, using a broad polyethylenestandard, as outlined in the section on Light Scattering (LS) GPC, belowin the paragraph following Equation (5). Use of this polyethylenecalibration method to obtain molecular weight values, such as themolecular weight distribution (MWD or Mw/Mn), and related statistics, isdefined here as the modified method of Williams and Ward. The numberaverage molecular weight, the weight average molecular weight, and thez-average molecular weight are calculated from the following equations.

$\begin{matrix}{{{Mw}_{CC} = {{\sum\limits_{i}{\left( \frac{C_{i}}{\sum\limits_{i}C_{i}} \right)M_{i}}} = {\sum\limits_{i}{w_{i}M_{{cc},i}}}}};} & \left( {{Eq}.\mspace{14mu} 2} \right) \\{{M_{n,{cc}} = {\sum{w_{i}/{\sum\left( {w_{i}/M_{{cc},i}} \right)}}}};} & \left( {{Eq}.\mspace{14mu} 3} \right) \\{M_{z,{cc}} = {\sum{\left( {w_{i}M_{{cc},i}^{2}} \right)/{\sum{\left( {w_{i}M_{{cc},i}} \right).}}}}} & \left( {{Eq}.\mspace{14mu} 4} \right)\end{matrix}$Light Scattering (LS) GPC

For the LS GPC, the Precision Detector PDI2040 detector Model 2040 isused. Depending on the sample, either the 15° angle or the 90° angle ofthe light scattering detector is used for calculation purposes. Here,the 15° angle was used.

The molecular weight data is obtained in a manner consistent with thatpublished by Zimm (Zimm, B. H., J. Chem. Phys., 16, 1099 (1948)) andKratochvil (Kratochvil, P., Classical Light Scattering from PolymerSolutions, Elsevier, Oxford, N.Y. (1987)). The overall injectedconcentration used in the determination of the molecular weight isobtained from the mass detector area, and the mass detector constantderived from a suitable linear polyethylene homopolymer, or one of thepolyethylene standards of known weight average molecular weight. Thecalculated molecular weights are obtained using a light scatteringconstant derived from one or more of the polyethylene standards,mentioned below, and a refractive index concentration coefficient,dn/dc, of 0.104. Generally, the mass detector response and the lightscattering constant should be determined from a linear standard with amolecular weight in excess of about 50,000 g/mole. The viscometercalibration can be accomplished using the methods described by themanufacturer, or, alternatively, by using the published values ofsuitable linear standards, such as Standard Reference Materials (SRM)1475a (available from National Institute of Standards and Technology(NIST)). The chromatographic concentrations are assumed low enough toeliminate addressing 2nd viral coefficient effects (concentrationeffects on molecular weight).

With 3D-GPC, absolute weight average molecular weight (“Mw, Abs”) isdetermined using Equation (5) below, using the “peak area” method forhigher accuracy and precision. The “LS Area” and the “Conc. Area” aregenerated by the chromatograph/detectors combination.

$\begin{matrix}{M_{W} = {{\sum\limits_{i}{w_{i}M_{i}}} = {{\sum\limits_{i}{\left( \frac{C_{i}}{\sum\limits_{i}C_{i}} \right)M_{i}}} = {\frac{\sum\limits_{i}{C_{i}M_{i}}}{\sum\limits_{i}C_{i}} = {\frac{\sum\limits_{i}{LS}_{i}}{\sum\limits_{i}C_{i}} = \frac{{LS}\mspace{14mu}{Area}}{{Conc}.\mspace{14mu}{Area}}}}}}} & \left( {{Eq}.\mspace{14mu} 5} \right)\end{matrix}$

For each LS and viscometry DP profile (for example, see FIGS. 1, 2, and3) the x-axis (log MWcc-CPC), where cc refers to the conventionalcalibration curve, is determined as follows. First, the polystyrenestandards (see above) are used to calibrate the retention volume into“log MW_(PS).” Then, Equation 1 (Mpolyethylene=A×(Mpolystyrene)^(B)) isused to convert “log MW_(PS)” to “log MW_(PE).” The “log MW_(PE)” scaleserves as the x-axis for the LS profiles of the experimental section(log MW_(PE) is equated to the log MW(cc-CPC)). The y-axis for each LSor DP profile is the LS or DP detector response normalized by theinjected sample mass. In FIGS. 1, 2 and 3, the y-axis for eachviscometer DP profile is the DP detector response normalized by theinjected sample mass. Initially, the molecular weight and intrinsicviscosity for a linear polyethylene standard sample, such as SRM1475a oran equivalent, are determined using the conventional calibrations (“cc”)for both molecular weight and intrinsic viscosity as a function ofelution volume.

gpcBR Branching Index by Triple Detector GPC (3D-GPC)

The gpcBR branching index is determined by first calibrating the lightscattering, viscosity, and concentration detectors as describedpreviously. Baselines are then subtracted from the light scattering,viscometer, and concentration chromatograms. Integration windows arethen set to ensure integration of all of the low molecular weightretention volume range in the light scattering and viscometerchromatograms that indicate the presence of detectable polymer from therefractive index chromatogram. Linear polyethylene standards are thenused to establish polyethylene and polystyrene Mark-Houwink constants.Upon obtaining the constants, the two values are used to construct twolinear reference conventional calibrations for polyethylene molecularweight and polyethylene intrinsic viscosity as a function of elutionvolume, as shown in Equations (6) and (7):

$\begin{matrix}{{M_{PE} = {\left( \frac{K_{PS}}{K_{PE}} \right)^{{1/\alpha_{PE}} + 1} \cdot M_{PS}^{\alpha_{PS} + {1/\alpha_{PE}} + 1}}},} & \left( {{Eq}.\mspace{14mu} 6} \right) \\{\lbrack\eta\rbrack_{PE} = {K_{{PS}\;} \cdot {M_{PS}^{\alpha + 1}/{M_{PE}.}}}} & \left( {{Eq}.\mspace{14mu} 7} \right)\end{matrix}$

The gpcBR branching index is a robust method for the characterization oflong chain branching as described in Yau, Wallace W., “Examples of Using3D-GPC—TREF for Polyolefin Characterization,” Macromol. Symp., 2007,257, 29-45. The index avoids the “slice-by-slice” 3D-GPC calculationstraditionally used in the determination of g′ values and branchingfrequency calculations, in favor of whole polymer detector areas. From3D-GPC data, one can obtain the sample bulk absolute weight averagemolecular weight (Mw, Abs) by the light scattering (LS) detector, usingthe peak area method. The method avoids the “slice-by-slice” ratio oflight scattering detector signal over the concentration detector signal,as required in a traditional g′ determination.

With 3D-GPC, sample intrinsic viscosities are also obtainedindependently using Equations (8). The area calculation in Equation (5)and (8) offers more precision, because, as an overall sample area, it ismuch less sensitive to variation caused by detector noise and 3D-GPCsettings on baseline and integration limits. More importantly, the peakarea calculation is not affected by the detector volume offsets.Similarly, the high-precision, sample intrinsic viscosity (IV) isobtained by the area method shown in Equation (8):

$\begin{matrix}{{{IV} = {\lbrack\eta\rbrack = {{\sum\limits_{i}{w_{i}{IV}_{i}}} = {{\sum\limits_{i}{\left( \frac{C_{i}}{\sum\limits_{i}C_{i}} \right){IV}_{i}}} = {\frac{\sum\limits_{i}{C_{i}{IV}_{i}}}{\sum\limits_{i}C_{i}} = {\frac{\sum\limits_{i}{DP}_{i}}{\sum\limits_{i}C_{i}} = \frac{{DP}\mspace{14mu}{Area}}{{Conc}.\mspace{14mu}{Area}}}}}}}},} & \left( {{Eq}.\mspace{14mu} 8} \right)\end{matrix}$where DPi stands for the differential pressure signal monitored directlyfrom the online viscometer.

To determine the gpcBR branching index, the light scattering elutionarea for the sample polymer is used to determine the molecular weight ofthe sample. The viscosity detector elution area for the sample polymeris used to determine the intrinsic viscosity (IV or [η]) of the sample.

Initially, the molecular weight and intrinsic viscosity for a linearpolyethylene standard sample, such as SRM1475a or an equivalent, aredetermined using the conventional calibrations (“cc”) for both molecularweight and intrinsic viscosity as a function of elution volume, perEquations (2) and (9):

$\begin{matrix}{\lbrack\eta\rbrack_{CC} = {{\sum\limits_{i}{\left( \frac{C_{i}}{\sum\limits_{i}C_{i}} \right){IV}_{i}}} = {\sum\limits_{i}{w_{i}{{IV}_{{cc},i}.}}}}} & \left( {{Eq}.\mspace{14mu} 9} \right)\end{matrix}$

Equation (10) is used to determine the gpcBR branching index:

$\begin{matrix}{{{gpcBR} = \left\lbrack {{\left( \frac{\lbrack\eta\rbrack_{CC}}{\lbrack\eta\rbrack} \right) \cdot \left( \frac{M_{W}}{M_{W,{CC}}} \right)^{\alpha_{PE}}} - 1} \right\rbrack},} & \left( {{Eq}.\mspace{14mu} 10} \right)\end{matrix}$wherein [η] is the measured intrinsic viscosity, [η]_(cc) is theintrinsic viscosity from the conventional calibration, Mw is themeasured weight average molecular weight, and M_(w,cc) is the weightaverage molecular weight of the conventional calibration. The weightaverage molecular weight by light scattering (LS) using Equation (5) iscommonly referred to as “absolute weight average molecular weight” or“M_(w), Abs.” The M_(w,cc) from Equation (2) using conventional GPCmolecular weight calibration curve (“conventional calibration”) is oftenreferred to as “polymer chain backbone molecular weight,” “conventionalweight average molecular weight,” and “M_(w,GPC).”

All statistical values with the “cc” subscript are determined usingtheir respective elution volumes, the corresponding conventionalcalibration as previously described, and the concentration (Ci). Thenon-subscripted values are measured values based on the mass detector,LALLS, and viscometer areas. The value of K_(PE) is adjustediteratively, until the linear reference sample has a gpcBR measuredvalue of zero. For example, the final values for α and Log K for thedetermination of gpcBR in this particular case are 0.725 and −3.355,respectively, for polyethylene, and 0.722 and −3.993, respectively, forpolystyrene.

Once the K and α values have been determined using the procedurediscussed previously, the procedure is repeated using the branchedsamples. The branched samples are analyzed using the final Mark-Houwinkconstants as the best “cc” calibration values, and Equations (2)-(9) areapplied.

The interpretation of gpcBR is straight forward. For linear polymers,gpcBR calculated from Equation (8) will be close to zero, since thevalues measured by LS and viscometry will be close to the conventionalcalibration standard. For branched polymers, gpcBR will be higher thanzero, especially with high levels of long chain branching, because themeasured polymer molecular weight will be higher than the calculatedM_(w,cc), and the calculated IV_(cc) will be higher than the measuredpolymer IV. In fact, the gpcBR value represents the fractional IV changedue to the molecular size contraction effect as a result of polymerbranching. A gpcBR value of 0.5 or 2.0 would mean a molecular sizecontraction effect of IV at the level of 50% and 200%, respectively,versus a linear polymer molecule of equivalent weight.

For these particular examples, the advantage of using gpcBR, incomparison to a traditional “g′ index” and branching frequencycalculations, is due to the higher precision of gpcBR. All of theparameters used in the gpcBR index determination are obtained with goodprecision, and are not detrimentally affected by the low 3D-GPC detectorresponse at high molecular weight from the concentration detector.Errors in detector volume alignment also do not affect the precision ofthe gpcBR index determination.

Representative Calculation of LS Profile “LSP”—Inventive and Comparative

A GPC elution profile of the concentration-normalized LS detectorresponse is shown in FIGS. 1 and 2 for Inventive Examples 1 and 2, andFIG. 3 for Comparative Example 1, respectively. The quantities thataffect the “LSP” value are defined with the aid of these Figures. Thex-axis in the plots is the logarithmic value of the molecular weight(MW) by conventional GPC calculation, or cc-GPC MW. The y-axis is the LSdetector response normalized for equal sample concentration, as measuredby the peak area of the concentration detector (not shown). The specificfeatures of the LS elution profile are captured in a window defined bytwo log-MW limits shown in the FIGS. 1 and 2. The lower limitcorresponds to a M1 value of 200,000 g/mol, and the upper limitcorresponds to a M2 value of 1,200,000 g/mol.

The vertical lines of these two MW limits intersect with the LS elutioncurve at two points. A line segment is drawn connecting these twointercept points. The height of the LS signal at the first intercept(log M1) gives the S1 quantity. The height of the LS signal at thesecond intercept (log M2) gives the S2 quantity. The area under the LSelution curve within the two MW limits gives the quantity Area B.Comparing the LS curve with the line segment connecting the twointercepts, there can be part of the segregated area that is above theline segment (see A2 in the Figures, defined as a negative value) orbelow the line segment (like A1 in the Figures, defined as a positivevalue). The sum of A1 and A2 gives the quantity Area A, the total areaof A. This total area A can be calculated as the difference between theArea B and the area below the line segment. The validity of thisapproach can be proven by the following two equations (note that A2 isnegative as shown in the FIGS. 1 and 2). Since, (Area below linesegment)=(Area B)+A2+A1=(Area B)+(Area A), therefore, (Area A)=(AreaB)−(Area below line segment).

The steps of calculating the “LSP” quantity are illustrated with threeexamples (Inventive Examples 1 and 2, and Comparative Example 1) shownin Table 1 and Table 2.

Step 1, calculate “SlopeF” in Table 1, using following two equations:slope_value=[(LS2−LS1)/LS2]/d Log M  (Eq. 11)SlopeF=a slope function=Abs(slope_value−0.42)+0.001  (Eq. 12)

Step 2, calculate “AreaF” and “LSF” in Table 2, using following twoequations:AreaF=an area function=Abs(Abs(A/B+0.033)−0.005)  (Eq. 13)where, A/B=(Area A)/(Area B)LSP=Log(AreaF*SlopeF)+4  (Eq. 14)

TABLE 1 The “SlopeF” Calculation M1 = 200,000 M2 = 1,200,000 Log(M2) −Abs(slope- g/mol g/mol Log(M1) 0.42) + Log Log dLog Slope 0.001 SampleLS1 M1 LS2 M2 M Value SlopeF Ex. 1 0.34 5.699 0.41 6.079 0.380 0.4180.003 Ex. 2 0.10 5.699 0.08 6.079 0.380 −0.57 0.989 CE 1 0.25 5.699 0.326.079 0.380 0.529 0.110

TABLE 2 The “AreaF” and “LSP” Calculation Line segment Abs(AbsLog(AreaF * LS curve Area (A/B + 0.033) − SlopeF) + Sample Area B (A +B) A/B 0.005) = AreaF 4 = LSP Ex. 1 24.801 25.76 0.039 0.0667 0.36 Ex. 2 6.791  6.54 −0.037 0.0012 1.07 CE 1 18.549 19.61 0.057 0.0851 1.97Differential Scanning Calorimetry (DSC)

Differential Scanning calorimetry (DSC) can be used to measure themelting and crystallization behavior of a polymer over a wide range oftemperatures. For example, the TA Instruments Q1000 DSC, equipped withan RCS (refrigerated cooling system) and an autosampler is used toperform this analysis. During testing, a nitrogen purge gas flow of 50ml/min is used. Each sample is melt pressed into a thin film at about175° C.; the melted sample is then air-cooled to room temperature (˜25°C.). The film sample was formed by pressing a “0.1 to 0.2 gram” sampleat 175° C. at 1,500 psi and 30 seconds, to form a “0.1 to 0.2 mil thick”film. A 3-10 mg, six mm diameter specimen is extracted from the cooledpolymer, weighed, placed in a light aluminum pan (ca 50 mg), and crimpedshut. Analysis is then performed to determine its thermal properties.

The thermal behavior of the sample is determined by ramping the sampletemperature up and down to create a heat flow versus temperatureprofile. First, the sample is rapidly heated to 180° C., and heldisothermal for five minutes, in order to remove its thermal history.Next, the sample is cooled to −40° C., at a 10° C./minute cooling rate,and held isothermal at −40° C. for five minutes. The sample is thenheated to 150° C. (this is the “second heat” ramp) at a 10° C./minuteheating rate. The cooling and second heating curves are recorded. Thecooling curve is analyzed by setting baseline endpoints from thebeginning of crystallization to −20° C. The heating curve is analyzed bysetting baseline endpoints from −20° C. to the end of melt. The valuesdetermined are peak melting temperature (T_(m)), peak crystallizationtemperature (T_(c)), heat of fusion (H_(f)) (in Joules per gram), andthe calculated % crystallinity for polyethylene samples using:% Crystallinity=((H _(f))/(292 J/g))×100  (Eq. 15).

The heat of fusion and the peak melting temperature are reported fromthe second heat curve. The peak crystallization temperature isdetermined from the cooling curve.

Film Testing

The following physical properties were measured on the films asdescribed in the experimental section.

Total (Overall) Haze and Internal Haze: Internal haze and total hazewere measured according to ASTM D 1003-07. Internal haze was obtainedvia refractive index matching using mineral oil (1-2 teaspoons), whichwas applied as a coating on each surface of the film. A Hazegard Plus(BYK-Gardner USA; Columbia, Md.) was used for testing. For each test,five samples were examined, and an average reported. Sample dimensionswere “6 in×6 in.”

45° Gloss: ASTM D2457-08 (average of five film samples; each sample “10in×10 in”).

Clarity: ASTM D1746-09 (average of five film samples; each sample “10in×10 in”).

2% Secant Modulus-MD (machine direction) and CD (cross direction): ASTMD882-10 (average of five film samples in each direction; each sample “1in×6 in”).

MD and CD Elmendorf Tear Strength: ASTM D1922-09 (average of 15 filmsamples in each direction; each sample “3 in×2.5 in” half moon shape).

MD and CD Tensile Strength: ASTM D882-10 (average of five film samplesin each direction; each sample “1 in×6 in”).

Dart Impact Strength: ASTM D1709-09 (minimum of 20 drops to achieve a50% failure; typically ten “10 in×36 in” strips).

Puncture Strength Puncture was measured on an INSTRON Model 4201 withSINTECH TESTWORKS SOFTWARE Version 3.10. The specimen size was “6 in×6in,” and four measurements were made to determine an average puncturevalue. The film was conditioned for 40 hours after film production, andat least 24 hours in an ASTM controlled laboratory (23° C. and 50%relative humidity). A “100 lb” load cell was used with a round specimenholder of 4 inch diameter. The puncture probe was a “½ inch diameter”polished stainless steel ball (on a 2.5″ rod) with a “7.5 inch maximumtravel length.”

There was no gauge length, and the probe was as close as possible to,but not touching, the specimen. The probe was set by raising the probeuntil it touched the specimen. Then the probe was gradually lowered,until it was not touching the specimen. Then the crosshead was set atzero. Considering the maximum travel distance, the distance would beapproximately 0.10 inch. The crosshead speed was 10 inches/minute. Thethickness was measured in the middle of the specimen. The thickness ofthe film, the distance the crosshead traveled, and the peak load wereused to determine the puncture by the software. The puncture probe wascleaned using a “KIM-WIPE” after each specimen.

Shrink Tension: Shrink tension was measured according to the methoddescribed in Y. Jin, T. Hermel-Davidock, T. Karjala, M. Demirors, J.Wang, E. Leyva, and D. Allen, “Shrink Force Measurement of Low ShrinkForce Films”, SPE ANTEC Proceedings, p. 1264 (2008). The shrink tensionof film samples was measured through a temperature ramp test that wasconducted on an RSA-III Dynamic Mechanical Analyzer (TA Instruments; NewCastle, Del.) with a film fixture. Film specimens of “12.7 mm wide” and“63.5 mm long” were die cut from the film sample, either in the machinedirection (MD) or the cross direction (CD), for testing. The filmthickness was measured by a Mitutoyo Absolute digimatic indicator (ModelC112CEXB). This indicator had a maximum measurement range of 12.7 mm,with a resolution of 0.001 mm. The average of three thicknessmeasurements, at different locations on each film specimen, and thewidth of the specimen, were used to calculate the film's cross sectionalarea (A), in which “A=Width×Thickness” of the film specimen that wasused in shrink film testing.

A standard film tension fixture from TA Instruments was used for themeasurement. The oven of the RSA-III was equilibrated at 25° C., for atleast 30 minutes, prior to zeroing the gap and the axial force. Theinitial gap was set to 20 mm. The film specimen was then attached ontoboth the upper and the lower fixtures. Typically, measurements for MDonly require one ply film. Because the shrink tension in the CDdirection is typically low, two or four plies of films are stackedtogether for each measurement to improve the signal-to-noise ratio. Insuch a case, the film thickness is the sum of all of the plies. In thiswork, a single ply was used in the MD direction and two plies were usedin the CD direction. After the film reached the initial temperature of25° C., the upper fixture was manually raised or lowered slightly toobtain an axial force of −1.0 g. This was to ensure that no buckling orexcessive stretching of the film occurred at the beginning of the test.Then the test was started. A constant fixture gap was maintained duringthe entire measurement.

The temperature ramp started at a rate of 90° C./min, from 25° C. to 80°C., followed by a rate of 20° C./min, from 80° C. to 160° C. During theramp from 80° C. to 160° C., as the film shrunk, the shrink force,measured by the force transducer, was recorded as a function oftemperature for further analysis. The difference between the “peakforce” and the “baseline value before the onset of the shrink forcepeak” is considered the shrink force (F) of the film. The shrink tensionof the film is the ratio of the shrink force (F) to the initial crosssectional area (A) of the film.

EXPERIMENTAL

Preparation of Inventive Ethylene-Based Polymers

FIG. 4 is a block diagram of the process reaction system used to producethe examples. The process reaction system in FIG. 4 is a partiallyclosed-loop, dual recycle, high-pressure, low density polyethyleneproduction system. The process reaction system is comprised of a freshethylene feed line [1], a booster/primary compressor “BP,” ahypercompressor “Hyper,” and a three zone tube. The tube reactorconsists of a first reaction feed zone; a first peroxide initiator line[3] connected to a first peroxide initiator source [11]; a secondperoxide initiator line [4] connected to the second peroxide initiatorsource 12; and a third peroxide initiator line [5] connected to a thirdperoxide initiator source 13. Cooling jackets (using high pressurewater) are mounted around the outer shell of the tube reactor andpreheater. The tube reactor further consists of a high pressureseparator “HPS,” a high pressure recycle line [7], a low pressureseparator “LPS,” a low pressure recycle line [9], and a chain transferagent (CTA) feed system 13.

The tube reactor further comprises three reaction zones demarcated bythe location of peroxide injection points. The first reaction zone feedis attached to the front of the tube reactor, and feeds a portion of theprocess fluid into the first reaction zone. The first reaction zonestarts at injection point #1 [3], and ends at injection point #2 [4].The first peroxide initiator is connected to the tube reactor atinjection point #1 [3]. The second reaction zone starts at injectionpoint #2 [4]. The second reaction zone ends at injection point #3 [5].The third reaction zone starts at injection point #3 [5]. For all theexamples, 100 percent of the ethylene and ethylene recycles are directedto the first reaction zone, via the first reaction zone feed conduit[1]. This is referred to as an all front gas tubular reactor.

For Inventive Example 1 and Comparative Example 1, a mixture containingt-butyl peroxy-2 ethylhexanoate (TBPO), di-t-butyl peroxide (DTBP),tert-butyl peroxypivalate (PIV), and an iso-paraffinic hydrocarbonsolvent (boiling range 171-191° C.; for example, ISOPAR H) are used asthe initiator mixture for the first injection point. For injectionpoints #2 and #3, a mixture containing only DTBP, TBPO, and theiso-paraffinic hydrocarbon solvent are used.

For Inventive Example 4, a mixture containing t-butylperoxy-2-ethylhexanoate (TBPO), di-t-butyl peroxide (DTBP), tert-butylperoxyneodecanoate (PND), and an iso-paraffinic hydrocarbon solvent(boiling range 171-191° C.; for example, ISOPAR H) are used as theinitiator mixture for the first injection point. For injection points #2and #3, a mixture containing only DTBP, TBPO, and the iso-paraffinichydrocarbon solvent are used. The reactor tube process conditions aregiven in Tables 3, 4 and 5.

Propylene was used as the CTA. The propylene was injected into theethylene stream at the discharge drum of the first stage booster. Theconcentration of the CTA feed to the process was adjusted to control themelt index of the product.

For Inventive Examples 1 and 4, it was discovered that these pressuresand temperatures produced a LDPE fractional melt index resin with abroad molecular weight distribution (MWD). Table 5 shows that thereactor pressure was lowered and the reactor peak temperatures wereraised for the Inventive Examples when compared to the ComparativeExample. This was done to maximize the molecular weight distribution ofthe product. The molecular weight of the examples was also maximized byreducing the recycle CTA (propylene) concentration fed to the reactor.These process conditions, along with other disclosed process conditions,result in resins with the inventive properties described herein.

Properties of inventive LDPEs and comparative LDPEs are listed in Tables6-11. Table 6 contains the melt index (I2), density, melt strength, andthe velocity at break of the melt strength data. The inventive polymersexhibit a good melt strength, but not as high as some of the comparativeexamples, and provide a good balance of bubble stability in combinationwith low gels in the final film, which is often formed from a blend of aLDPE with another material such as LLDPE. If the melt strength is toohigh, there is a higher propensity to form gels, and also the resin whenused in film applications may not be able to be drawn down to thinthicknesses.

Table 6 also contains the conventional TDGPC data, illustrating for theinventive examples the relatively broad molecular weight distribution orMWD or cc-GPC Mw/Mn, and relatively high z-average molecular weight, Mzor cc-GPC Mz. Table 7 contains the TDGPC-related properties derived fromthe LS and viscosity detectors, in conjunction with the concentrationdetector, showing that the inventive examples have an intermediateMw-abs, Mw(LS-abs)/Mw(cc-GPC), and gpcBR, and a low LSP, reflective ofthe relatively broad molecular weight distribution, coupled with arelatively high level of long chain branching, as reflected by a highgpcBR. This design is optimized to give an optimum melt strength, inorder to give a good balance of physical properties, along with gooddrawability, bubble stability, output, and processability, when formingfilms or coatings with an inventive LDPE or blends with this LDPE.

Table 8 contains the DMS viscosity data, as summarized by theviscosities measured at 0.1, 1, 10, and 100 rad/s, the viscosity ratioor the ratio of viscosity measured at 0.1 rad/s to the viscositymeasured at 100 rad/s, all being measured at 190° C., and the tan deltameasured at 0.1 rad/s. The low frequency viscosity, the viscosity at 0.1rad/s, is relatively high for the Inventive Examples as compared to theComparative Examples. A high “low frequency viscosity” may be correlatedwith good melt strength, bubble stability, and film output. Theviscosity ratio, which reflects the change in viscosity with frequency,is high for the Inventive Examples as compared to the ComparativeExamples. This is reflective of potentially good processability of theInventive Examples when making blown film. The tan delta at 0.1 rad/s isrelatively low, indicative of high melt elasticity, which may also becorrelated with good blown film bubble stability.

Table 9 contains the branches per 1000C as measured by ¹³C NMR. TheseLDPE polymers contain amyl, or C5 branches, which are not contained insubstantially linear polyethylenes, such as AFFINITY PolyolefinPlastomers, or the LLDPEs, such as DOWLEX Polyethylene Resins, bothproduced by The Dow Chemical Company. Each inventive and comparativeLDPE, shown in Table 9, contains greater than, or equal to, 0.5 amylgroups (branches) per 1000 carbon atoms (the Inventive Examples containgreater than 1 amyl groups (branches) per 1000 carbon atoms).

Table 10 contains unsaturation results by ¹H NMR. Table 11 contains theDSC results of the melting point, T_(m), the heat of fusion, the percentcrystallinity, and the crystallization point, T_(c).

TABLE 3 Peroxide initiator flows in pounds per hour at each injectionpoint used for manufacture of Examples 2-5. Example 2 Example 3 Example4 Example 5 Injection Neat PO Neat PO Neat PO Neat PO Point Initiatorlbs/hour lbs/hour lbs/hour lbs/hour #1 TBPO 3.6 3.8 3.9 3.6 #1 DTBP 2.62.5 2.4 2.4 #1 PND 0.58 0.60 0.55 0.60 #2 TBPO 0.95 0.96 0.91 0.90 #2DTBP 4.1 4.0 4.1 4.1 #3 TBPO 0.66 0.65 0.65 0.65 #3 DTBP 1.3 1.4 1.3 1.3

TABLE 4 Peroxide initiator flows in pounds per hour at each injectionpoint used for manufacture of Example 1 and Comparative Example 1.Comparative Injection Example 1 Example 1 Point Initiator (kg/hr)(kg/hr) #1 TBPO 3.32 2.67 #1 DTBP 0.86 0.69 #1 PIV 0.74 0.59 #1 Solvent19.70 15.83 #2 TBPO 0.24 0.21 #2 DTBP 0.73 0.63 #2 Solvent 11.23 9.71 #3TBPO 0.30 0.22 #3 DTBP 0.90 0.65 #3 Solvent 13.73 9.98

TABLE 5 Process conditions used to manufacture Inventive Examples 1-5and Comparative Example 1. Comp. Process Variables Ex. 1 Ex. 2 Ex. 3 Ex.4 Ex. 5 Ex. 1 Reactor Pressure 35,000 36,000 36,000 36,000 36,000 38,000(Psig) Zone 1 Initiation T 132 154 154 154 154 134 (° C.) Zone 1 Peak T(° C.) 302 305 305 305 305 298 Zone 2 Initiation T 251 225 225 224 224246 (° C.) Zone 2 Peak T (° C.) 302 305 305 305 305 298 Zone 3Initiation T 255 248 247 247 248 246 (° C.) Zone 3 Peak T (° C.) 299 285285 285 285 292 Fresh ethylene Flow 24,901 29,500 29,500 29,500 29,50024,160 (lb/hr) Ethylene Throughput 101,000 100,000 100,000 100,000100,000 101,000 to Reactor (lb/hr) Ethylene Conversion 23 28 28 28 2823.6 (%) Polyethylene 23,202 28,000 28,000 28,000 28,000 23,800Production Rate (lb/hr) Propylene Flow 134 268 266 266 260 233 (lb/hr)Ethylene Purge Flow 488 1,500 1,500 1,500 1,500 490 (lb/hr) Recycle PropConc. 0.33 0.63 0.63 0.63 0.63 0.83 (% Vol) Pre-heater T (° C.) 206 190190 190 190 206 Reactor Cooling 183 140 140 140 140 183 System 1 (° C.)Reactor Cooling 183 N/A N/A N/A N/A 183 System 2 (° C.)

TABLE 6 Melt Index (I2), Density, Melt Strength (MS) and Velocity atBreak at 190° C. and TDGPC-related properties (conventional calibration)of Examples and Comparative Examples. Melt Velocity cc-GPC cc-GPC cc-GPCI₂ Density strength at break Mn Mw Mz cc-GPC Sample (190° C.) (g/cc)(cN) (mm/s) (g/mol) (g/mol) (g/mol) Mw/Mn Ex. 1 0.15 0.9195 17.0 65.018,287 121,843 395,621 6.66 Ex. 2 0.15 0.9183 18.6 62.7 18,726 130,231387,249 6.95 Ex. 3 0.15 0.9183 18.3 52.9 18,605 130,532 392,440 6.96 Ex.4 0.15 0.9184 17.8 54.7 18,725 130,255 384,698 6.96 Ex. 5 0.15 0.918519.1 59.9 18,736 131,327 392,865 7.01 CE 1 0.25 0.9228 15.0 102.0 20,332106,549 334,953 5.24 CE 2 0.17 0.9184 19.5 54.0 19,835 141,700 451,8547.18 CE 3 0.38 0.9182 30.0 72.0 24,050 255,596 901,799 10.63 CE 4 0.640.9205 12.1 162.0 15,463 101,916 330,862 6.59 CE 5 0.44 0.9244 11.5172.0 20,044 87,096 262,188 4.35 CE 6 0.37 0.9276 12.6 116.0 20,43290,529 261,099 4.43 CE 7 0.24 0.9215 15.1 53.0 18,327 108,779 344,2745.94 CE 8 0.49 0.9274 11.8 91.0 20,111 102,166 345,225 5.08 CE 9 0.630.9262 11.6 133.0 18,194 98,424 340,388 5.41 CE 10 0.70 0.9269 11.6153.0 18,703 100,434 350,396 5.37 CE 11 0.23 0.9189 21.8 54.0 19,504129,761 405,912 6.65 CE 12 0.26 0.9179 25.8 47.0 18,406 141,179 451,3487.67 CE 13 0.26 0.9251 18.6 74.0 22,343 106,907 267,377 4.78 CE 14 0.850.9240 13.1 237.0 17,895 93,157 293,489 5.21 CE 15 0.17 0.9225 16.6 62.019,379 114,951 385,618 5.93 CE 16 0.61 0.9269 13.4 124.0 17,287 101,768333,400 5.89 CE 17 1.08 0.924 10.2 335 20,412 84,867 192,476 4.16 CE 180.82 0.923 16.5 273 20,224 98,856 253,926 4.89 CE 19 0.25 0.9200 17.4 7817,199 114,533 376,996 6.66 CE 20 0.90 0.9328 6.5 274 24,463 65,652135,683 2.68 CE 21 0.15 0.9200 19.37 53.3 17,160 125,170 319,287 7.29 CE22 0.39 0.9190 16.21 74 12,727 112,867 304,980 9.31 CE 23 0.28 0.927815.6 70 18,431 109,716 354,514 5.95 CE 24 0.73 0.9236 16.18 183 22,545105,649 274,411 4.69 CE 25 0.70 0.9235 10.76 132.2 18,535 86,468 280,3304.67 CE 26 2.12 0.9178 16.5 228.8 18,491 169,817 631,298 9.18

TABLE 7 TDGPC-related properties (derived from LS and viscositydetectors in conjunction with the concentration detector). Mw-absMw(LS-abs)/ IVw IVcc IVcc/ LSP = Log Sample (g/mol) Mw(cc-GPC) (dl/g)gpcBR (dl/g) IVw LSCDF + 4 Ex. 1 268,302 2.20 1.13 1.80 1.85 1.65 0.36Ex. 2 273,105 2.10 1.16 1.91 1.95 1.68 1.07 Ex. 3 276,207 2.12 1.16 1.961.95 1.68 1.05 Ex. 4 276,601 2.12 1.16 1.96 1.95 1.68 1.30 Ex. 5 281,7162.15 1.17 1.98 1.96 1.68 0.71 CE 1 225,633 2.12 1.08 1.61 1.70 1.58 1.97CE 2 336,652 2.34 1.19 2.30 2.08 1.75 1.75 CE 3 951,706 3.72 1.27 5.273.04 2.38 2.88 CE 4 211,371 2.07 1.00 1.79 1.63 1.63 2.10 CE 5 164,2841.89 1.01 1.36 1.49 1.48 2.33 CE 6 184,461 2.04 1.02 1.57 1.54 1.50 2.49CE 7 225,070 2.07 1.08 1.73 1.72 1.59 2.04 CE 8 180,442 1.77 1.06 1.351.63 1.54 2.79 CE 9 181,596 1.85 1.02 1.44 1.58 1.55 2.76 CE 10 190,5691.90 1.03 1.48 1.60 1.56 2.80 CE 11 290,561 2.24 1.14 2.10 1.94 1.712.06 CE 12 316,844 2.24 1.15 2.22 2.05 1.78 1.69 CE 13 184,786 1.73 1.101.39 1.74 1.59 3.67 CE 14 195,785 2.10 0.98 1.72 1.55 1.58 1.78 CE 15257,569 2.24 1.11 1.90 1.78 1.60 2.08 CE 16 182,589 1.79 1.02 1.46 1.631.61 2.91 CE 17 124,474 1.47 0.96 1.07 1.49 1.55 4.63 CE 18 154,163 1.561.00 1.29 1.64 1.63 4.33 CE 19 266,655 2.33 1.07 2.11 1.77 1.66 1.75 CE20 97,247 1.48 0.97 0.72 1.27 1.31 4.22 CE 21 278,963 2.23 1.18 1.961.93 1.64 4.23 CE 22 275,647 2.33 1.08 2.20 1.81 1.68 4.25 CE 23 208,4521.90 1.08 1.55 1.72 1.60 3.14 CE 24 199,066 1.88 1.04 1.65 1.72 1.663.43 CE 25 148,996 1.72 1.00 1.18 1.46 1.46 2.41 CE 26 514,477 3.03 1.053.79 2.26 2.14 2.54

TABLE 8 Viscosities in Pa · s at 0.1, 1, 10, and 100 rad/s, theviscosity ratio, and the tan delta at 190° C. Vis. Ratio Tan Visc 0.1Visc 1 Visc 10 Visc 100 V0.1/ Delta Sample rad/s rad/s rad/s rad/s V1000.1 rad/s Ex. 1 47,750 15,519 3,989 882 54.1 1.3 Ex. 2 50,932 15,5323,865 830 61.4 1.2 Ex. 3 52,171 16,046 4,002 861 60.6 1.2 Ex. 4 50,58515,508 3,864 830 60.9 1.2 Ex. 5 51,410 15,676 3,898 836 61.5 1.2 CE 136,053 13,262 3,680 855 42.2 1.6 CE 2 44,635 14,203 3,672 816 54.7 1.2CE 3 21,127 8,089 2,470 639 33.0 1.6 CE 4 20,309 8,480 2,566 635 32.02.0 CE 5 27,013 11,419 3,492 858 31.5 2.0 CE 6 28,266 12,057 3,723 91331.0 2.1 CE 7 40,705 14,261 3,849 863 47.2 1.5 CE 8 24,204 10,186 3,178811 29.8 2.0 CE 9 19,811 8,715 2,835 736 26.9 2.1 CE 10 19,105 8,4242,742 713 26.8 2.1 CE 11 40,473 13,554 3,600 823 49.2 1.3 CE 12 37,94412,276 3,206 730 52.0 1.3 CE 13 37,164 14,111 4,034 939 39.6 1.7 CE 1416,593 7,709 2,542 663 25.0 2.4 CE 15 47,127 15,488 4,024 881 53.5 1.3CE 16 22,066 9,470 2,985 751 29.4 2.1 CE 17 11,627 6,437 2,377 666 17.53.8 CE 18 17,063 7,810 2,546 667 25.6 2.3 CE 19 34,788 12,138 3,289 75845.9 1.4 CE 20 10,755 6,638 2,652 786 13.7 4.8 CE 21 53,524 17,221 4,406953 56.2 1.3 CE 22 28,178 10,815 3,125 741 38.0 1.7 CE 23 36,174 13,6023,899 914 39.6 1.6 CE 24 16,153 8,048 2,803 751 21.5 2.9 CE 25 19,3888,702 2,860 749 25.9 0.7 CE 26 6,250 3,236 1,244 384 16.3 2.9

TABLE 9 Branching results in branches per 1000C by ¹³C NMR of Examplesand Comparative Examples. 1,3 diethyl C2 on Quat Sample C1 branchesCarbon C4 C5 C6+ Ex. 1 1.50 3.80 1.30 6.50 2.10 2.90 Ex. 2 1.83 3.76 122 6.76 1.78 2.75 Ex. 3 2.06 4.09 1.26 6.86 1.62 2.37 Ex. 4 2.09 4.231.29 6.80 1.58 2.11 Ex. 5 2.18 3.97 1.20 6.91 1.60 2.35 CE 1 2.50 3.100.80 5.80 2.10 3.10 CE 27*** ND ND ND ND ND 19.5* CE 28**** ND ND ND NDND 11.4* *The values in the C6+ column for the DOWLEX and AFFINITYsamples represent C6 branches from octene only, and do not include chainends. **ND = not detected.. ***AFFINITY PL 1880. ****DOWLEX 2045G

TABLE 10 Unsaturation results by ¹H NMR of Examples and ComparativeExamples. cis and total vinyl/ trans/ trisub/ vinylidene/ unsaturation/Sample 1000C 1000C 1000C 1000C 1000C Ex. 1 0.124 0.044 0.075 0.164 0.41Ex. 2 0.132 0.042 0.051 0.195 0.42 Ex. 3 0.148 0.049 0.085 0.205 0.49Ex. 4 0.153 0.052 0.095 0.210 0.51 Ex. 5 0.164 0.060 0.128 0.214 0.57 CE1 0.147 0.057 0.061 0.089 0.35 CE 27*** 0.040 0.064 0.123 0.043 0.27 CE28**** 0.283 0.049 0.042 0.055 0.43 ***AFFINITY PL 1880 ****DOWLEX 2045G

TABLE 11 DSC results of Examples and Comparative Examples. Heat of %Sample T_(m) (° C.) Fusion (J/g) Crystallinity T_(c) (° C.) Ex. 1 110.5141.8 48.6 97.8 Ex. 2 108.7 146.4 50.1 96.0 Ex. 3 108.5 147.9 50.7 96.1Ex. 4 108.5 147.0 50.3 96.2 Ex. 5 108.8 148.4 50.8 96.2Formulations

Blown films were made, and physical properties measured, with differentLDPEs and one LLDPE (LLDPE1 (DOWLEX 2045G)). LLDPE1 had a “1.0 meltindex (MI or I2), and a 0.920 g/cc density.” Films were made at 20 wt %and 80 wt % of the respective LDPE, based on the weight of the LDPE andLLDPE1.

Each formulation was compounded on a MAGUIRE gravimetric blender. Apolymer processing aid (PPA), DYNAMAR FX-5920A, was added to eachformulation. The PPA was added at “1.125 wt % of masterbatch,” based onthe total weight of the weight of the formulation. The PPA masterbatch(Ingenia AC-01-01, available from Ingenia Polymers) contained 8 wt % ofDYNAMAR FX-5920A in a polyethylene carrier. This amounts to 900 ppm PPAin the polymer.

LLDPE1 was also used as the LLDPE in the films made at maximum output.All samples were made with 80 wt % DOWLEX 2045G and 20 wt % LDPE.

Production of Blown Films

The monolayer blown films were made on an “8 inch die” with apolyethylene “Davis Standard Bather II screw.” External cooling by anair ring and internal bubble cooling were used. General blown filmparameters, used to produce each blown film, are shown in Table 12. Thetemperatures are the temperatures closest to the pellet hopper (Barrel1), and in increasing order, as the polymer was extruded through thedie.

TABLE 12 Blown film fabrication conditions for films. % LDPE 20 80 Blowup ratio (BUR) 2.5 2.5 Film thickness 2.0 2.0 Die gap (mil) 70 70 Airtemperature (° F.) 45 45 Temperature profile (° F.) Barrel 1 350 375Barrel 2 415 465 Barrel 3 365 440 Barrel 4 305 425 Barrel 5 305 425Screen Temperature 410 460 Adapter 410 460 Block 430 460 Lower Die 440460 Inner Die 440 460 Upper Die 440 460Production of Films for Determination of Maximum Output Rate of BlownFilm

Film samples were made at a controlled rate and at a maximum rate. Thecontrolled rate was 250 lb/hr, which equals an output rate of 10.0lb/hr/inch of die circumference. The die diameter used for the maximumoutput trials was an 8 inch die, so that for the controlled rate, as anexample, the conversion between “lb/hr” and “lb/hr/inch” of diecircumference, is shown in Equation 16. Similarly, such an equation canbe used for other rates, such as the maximum rate, by substituting themaximum rate in Equation 16 to determine the “lb/hr/inch” of diecircumference.Lb/Hr/Inch of Die Circumference=(250 Lb/Hr)/(8*π)=10  (Eq. 16)

The maximum rate for a given sample was determined by increasing theoutput rate to the point where bubble stability was the limiting factor.The extruder profile was maintained for both samples (standard rate andmaximum rate), however the melt temperature was higher for the maximumrate samples, due to the increased shear rate with higher motor speed(rpm, revolutions per minute). The maximum bubble stability wasdetermined by taking the bubble to the point where it would not stayseated in the air ring. At that point, the rate was reduced to where thebubble was reseated in the air ring, and then a sample was collected.The cooling on the bubble was adjusted by adjusting the air ring andmaintaining the bubble. This was taken as the maximum output rate, whilemaintaining bubble stability.

Film and extrusion coating drawdown properties are listed in Tables13-14. As seen in Table 13, it has been discovered that the InventiveExamples have excellent optics of haze, gloss, and clarity, compared tothe highest melt strength blend (Film #1) and (Film #5) at standard andmaximum output rates. All “Inventive Example blend films” have similartoughness in terms of tear, dart, and puncture, compared to theComparative Example blends, at standard and maximum rates, which isimportant, as it is desired to maintain toughness, while enhancingoutput. The Inventive Examples Film #6 and Film #7 have improved maximumoutput over Film #8.

As seen in Table 14, it has been discovered that the Inventive Examplesused in Films #10 and #11 have excellent optics of haze, gloss, andclarity compared to the highest melt strength (Film #9) at standardoutput rates. All “Inventive Example blend films” have similar orimproved toughness, in terms of tear and puncture, compared to thehighest melt strength (Film #9), at standard rates, which is important,as it is desired to maintain toughness, while enhancing output. Inaddition, the Inventive Films #10 and #11 have significantly improved(greater than 15%) dart compared to all the other film blends.

TABLE 13 Film properties of 80% LLDPE1/20% LDPE Films #1-8 made at 2 milat a standard (std.) rate of 250 lb/hr and at a maximum (max.) rate (8″die). Film 1 2 3 4 5 6 7 8 Component 1 LLDPE1 LLDPE1 LLDPE1 LLDPE1LLDPE1 LLDPE1 LLDPE1 LLDPE1 Wt % 80 80 80 80 80 80 80 80 Component 1Component 2 CE 3 Ex. 1 Ex. 3 CE 7 CE 3 Ex. 1 Ex. 3 CE 7 Wt % 20 20 20 2020 20 20 20 Component 2 Blown Film Std. Std. Std. Std. Max. Max. Max.Max. Rate Haze (%) 19.5 8.5 10.2 8.3 17.9 9.1 9.7 8.6 Haze, Internal 2.72.6 2.7 2.6 2.8 2.6 2.7 3.1 (%) 45 Degree 33.7 63.7 58.1 66.6 37.7 62.459.8 65.8 Gloss (%) Clarity (%) 75.6 96.2 93.3 97.3 79.2 97.1 94.3 97.6MD Tear (g) 423 376 333 368 365 449 333 436 CD Tear (g) 1,254 1,4521,320 1,467 1,315 1,460 1,437 1,456 Normalized MD 210 182 165 183 176223 165 220 Tear (g/mil) Normalized CD 617 710 669 750 640 725 705 746Tear (g/mil) Dart A (g) 253 295 286 286 235 286 268 295 Puncture 198 222224 223 206 214 220 225 (ft-lb_(f)/in³) 2% MD Secant 29,964 29,08330,781 29,656 30,341 31,024 31,193 29,102 Modulus (psi) 2% CD Secant37,613 33,215 37,856 34,758 37,507 35,791 36,828 33,776 Modulus (psi) MDShrink 14.5 10.8 14.8 10.5 16.8 12.0 14.3 10.9 Tension (psi) CD Shrink0.2 0.5 0.4 0.3 0.4 0.3 0.3 0.2 Tension (psi) Thickness (mil) 2.06 2.061.98 1.93 2.05 2.02 1.96 1.91 Frost Line 33 33 33 33 74 69 67 56 Height(inches) Melt Temperature 406 405 406 404 448 433 437 430 (° F.) RateOutput 249 251 253 253 491 415 422 405 (lb/hr) Rate Output 9.9 10.0 10.110.1 19.5 16.5 16.8 16.1 (lb/hr/in)

TABLE 14 Film properties of 20% LLDPE1/80% LDPE Films #9-13 made at 2mil at a standard (std.) rate of 250 lb/hr (8″ die). Film 9 10 11 12 13Component 1 LLDPE1 LLDPE1 LLDPE1 LLDPE1 LLDPE1 Wt % 20 20 20 20 20Component 1 Component 2 CE 3 Ex. 1 Ex. 3 CE 7 CE 5 Wt % 80 80 80 80 80Component 2 Haze (%) 40.0 13.8 16.5 10.7 9.9 Haze, Internal 1.8 1.7 3.31.9 5.1 (%) 45 Degree 14.5 43.8 39.2 52.5 65.8 Gloss (%) Clarity (%)41.5 83.7 79.3 88.6 94.9 MD Tear (g) 158 207 189 240 251 CD Tear (g) 329420 409 410 611 Normalized MD 74 98 88 114 125 Tear (g/mil) NormalizedCD 154 196 188 200 303 Tear (g/mil) Dart A (g) 184 217 220 160 133Puncture 72 108 97 91 87 (ft-lb_(f)/in³) 2% MD Secant 30,240 31,57430,228 30,152 33,134 Modulus (psi) 2% CD Secant 34,452 37,313 35,41835,261 37,587 Modulus (psi) MD Shrink 38.1 30.9 34.3 28.2 20.5 Tension(psi) CD Shrink 0.4 0.7 0.5 0.6 0.7 Tension (psi) Thickness (mil) 2.112.13 2.17 2.07 2.01 Frost Line 30 30 30 30 31 Height (inches) Melt 453468 467 465 463 Temperature (° F.) Rate Output 250 249 249 254 251(lb/hr) Rate Output 9.9 9.9 9.9 10.1 10.0 (lb/hr/in)

The invention claimed is:
 1. A composition comprising an ethylene-basedpolymer, which is a low density polyethylene (LDPE), obtained by freeradical polymerization of ethylene, and wherein the LDPE has a GPC-lightscattering parameter “LSP” less than 1.60; and wherein the polymer has aviscosity ratio (V0.1/V100, at 190° C.) greater than
 50. 2. Thecomposition of claim 1, wherein the LDPE has a gpcBR value from 1.50 to2.25.
 3. The composition of claim 1, wherein the polymer has a meltstrength greater than 15 cN and less than 25 cN.
 4. The composition ofclaim 1, wherein the polymer has a MWD(conv) from 5 to
 8. 5. Thecomposition of claim 1, wherein the polymer has a melt index (I2) from0.01 to 1 g/10 min.
 6. The composition of claim 1, wherein the polymerhas a density from 0.910 to 0.940 g/cc.
 7. The composition of claim 1,wherein the polymer has a melt strength of at least 15 cN and less than21 cN, and a velocity at break of greater than 40 mm/s.
 8. Thecomposition of claim 1, wherein the polymer has a MWD(conv) greater than6.
 9. The composition of claim 1, wherein the polymer is a low densitypolyethylene (LDPE), obtained by high pressure, free radicalpolymerization of ethylene.
 10. An article comprising at least onecomponent formed from the composition of claim
 1. 11. The article ofclaim 10, wherein the article is a film.
 12. The article of claim 10,wherein the article is selected from mono or multilayer films, moldedarticles, coatings, fibers, or woven or non-woven fabrics.
 13. Acomposition comprising an ethylene-based polymer that comprises thefollowing features: a) at least 0.1 amyl groups per 1000 total carbonatoms; b) a melt viscosity ratio (V0.1/V100, at 190° C.) greater than orequal to 58; c) a melt viscosity at 0.1 rad/s, 190° C., greater than orequal to 40,000 Pa·s, and d) a gpcBR value from 1.50 to 2.25.
 14. Anarticle comprising at least one component formed from the composition ofclaim
 13. 15. The article of claim 14, wherein the article is selectedfrom mono or multilayer films, molded articles, coatings, fibers, orwoven or non-woven fabrics.